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Öğe A comparative study of amino acid, mineral and vitamin profiles of milk from Turkish Saanen, Hair and Maltese goat breeds throughout lactation(Wiley, 2021) Günay, Emine; Güneşer, Onur; Karagül Yüceer, YoncaThis study aimed to evaluate the changes in nutritional compounds such as amino acids, minerals, and vitamins in the milk of Turkish Saanen, Hair and Maltese goat breeds. The Turkish Saanen goat breed had lower dry matter, fat, nitrogen, and vitamins A, E and B-2 than Maltese and Hair goat breeds throughout lactation period. High levels of proline, leucine, glutamic acid, and glutamine were found in all breeds. Except for tyrosine, all other amino acids were higher in Hair goat milk than those in other breed milk. The calcium content of the samples ranged from 1164.79 to 1214.16 mg/L.Öğe Aromatic and Sensorial Properties of Çökelek Cheese Produced by Different Methods(2019) Gün, İlhan; Güneşer, Onur; Karagül Yüceer, Yonca; Güzel Seydim, Zeynep Banu; Torun, Fatma; Çakıcı, SevdaN this study, it was aimed to reveal aroma-active compounds andensory properties of Çökelek cheese made from milk, yogurt and Tuluk yogurt. For this purpose, aroma active compounds in Çökelek samples were determinedby Gas Chromatography-Olfactometry. Furthermore, sensory properties of cheesesamples were determined by Spectrum® analysis. As result, 17 identified and 2unknown aroma active compounds were determined in Çökelek samples. Butyricacid, Furaneol® and sotolon were identified at high intensities in all cheeses. Itwas determined that the intensity of butyric acid was higher in Çökelek made fromyogurt while the intensities of Furaneol® and sotolon were found to be higher inÇökelek made from milk. “Cooked”, “Whey”, “Creamy”, “Rancid” “Fermented”,“Yeast”, “Sour”, “Salty”, “Sweet” and “Umami” were defined as characteristicsensory terms for Çökelek cheeses. It was determined that cooked, creamy andsweet were perceived in Çökelek made from yogurt while yeast aroma was foundto be a higher in Çökelek made from Tuluk yogurt.Öğe Bioflavour production from tomato and pepper pomaces by Kluyveromyces marxianus and Debaryomyces hansenii(Springer, 2015) Güneşer, Onur; Demirkol, Aslı; Karagül Yüceer, Yonca; Özmen Togay, Sine; İşleten Hoşoğlu, Müge; Elibol, MuratBioflavours are called natural flavour and/or fragrance compounds which are produced using metabolic pathway of the microorganism and/or plant cells or their enzyme systems with bioengineering approaches. The aim of this study was to investigate bioflavour production from tomato and red pepper pomaces by Kluyveromyces marxianus and Debaryomyces hansenii. Obtained specific growth rates of K. marxianus and D. hansenii in tomato pomace were 0.081/h and 0.177/h, respectively. The bioflavour profile differed between the yeasts. Both yeasts can produce esters and alcohols such as phenyl ethyl alcohol, isoamyl alcohol, isoamyl acetate, phenyl ethyl acetate and isovaleric acid. Tarhana and rose were descriptive flavour terms for tomato and pepper pomaces fermented by K. marxianus, respectively. Tomato pomace fermented by D. hansenii had the most intense green bean flavour while fermented vegetable and storage/yeast were defined as characteristic flavour terms for pepper pomaces fermented by D. hansenii.Öğe Biosynthesis of eight-carbon volatiles from tomato and pepper pomaces by fungi: Trichoderma atroviride and Aspergillus sojae(Soc Bioscience Bioengineering Japan, 2017) Güneşer, Onur; Karagül Yüceer, YoncaThe aim of this study was to investigate the possibility of using tomato and red pepper pomaces for the production eight-carbon volatiles by Trichoderma atroviride and Aspergillus sojae. The fermentation of tomato and pepper pomace based media by both moulds was conducted in shake flasks and bioreactors. Microbial growth behaviours and fermentation abilities of T. atroviride and A. sojae under both fermentation conditions were followed by microbial counting. The production of flavours from tomato and pepper pomaces by fungal metabolism was determined by gas chromatography olfactometry, gas chromatography-mass spectrometry and sensory analysis. The results showed that T. atroviride grew faster than A. sojae, and the survival of T. atroviride in the tomato pomace was longer than that of A. sojae. However, T. atroviride grew slower than A. sojae in the pepper pomace. Eight-carbon flavour compounds, including (Z)-1,5-octadien-3-ol, 1-octen-3-ol, (E)-2-octenal and (E)-2-octenol, were produced by T. atroviride and A. sojae from the tomato and pepper pomaces. The highest production levels (265.55 +/- 2.79 and 187.47 +/- 0.92 mu g kg(-1)) were observed for 1-octen-3-ol in the tomato fermentation by T. atroviride and A. sojae, respectively. The relationships between volatile compounds and their flavour characteristics in tomato and pepper pomaces were analysed using principal component analysis. (C) 2017, The Society for Biotechnology, Japan. All rights reserved.Öğe Changes in milk fatty acid composition of goats during lactation in a semi-intensive production system(Archiv Fur Tierzucht, 2009) Ataşoğlu, Cengiz; Uysal Pala, Çiğdem; Karagül Yüceer, YoncaThis study aimed at investigating changes in the fatty acid (FA) profile and conjugated linoleic acid (CLA) concentration of milk fat during lactation from goats managed in a semi-intensive production system, which consisted of grazing on a woody and herbaceous pasture with the supplementation of mixed concentrate and vetch hay. A total of 21 lactating goats were used. Milk samples were collected at different periods (25 April, 29 June, 25 August and 4 October) during lactation and analysed for their chemical composition and FA profile. The most abundant FA in the milk fat of goats was palmitic (06:0) acid, followed by oleic (C18:1 n-9), stearic (C18:0), capric (C10:0) and myristic (04:0) acids. These acids accounted for about 88% of the total milk FA of goats in all sampling periods. The two medium chain FA; capric (P=0.0001) and lauric (C12:0; P=0.0014) acid were affected by the sampling period, whereas myristic (P=0.4469) and palmitic (P=0.4418) acids did not change. Stearic (P=0.0128), oleic (P=0.0001), linoleic (C18:2; P=0.0088) and linolenic (C18:3; P=0.0001) acids also exhibited significant variations between the sampling periods. However, the CLA (C18:2 c9, t11 and C18:2 00, c12) contents of milk fat did not change during the entire study regardless of the sampling period (P=0.2448). Milk fatty acid composition of goats, which meet a major part of their nutrient requirements through grazing or browsing in a natural pasture, shows a seasonal variation with milk fat in summer representing a better fatty acid profile for product quality.Öğe Characterisation of aroma-active compounds, chemical and sensory properties of acid-coagulated cheese: Circassian cheese(Wiley, 2011) Güneşer, Onur; Karagül Yüceer, YoncaThe objectives of this study were to determine basic composition, aroma and sensory characteristics of Circassian cheese. Seven Circassian cheeses were provided by local producers. Aroma compounds were extracted by using solid-phase microextraction procedure and determined by gas chromatography-olfactometry system. Water-soluble, trichloroacetic acid-soluble and phosphotungstic acid-soluble nitrogen fractions ranged between 2.30-29.35%, 2.48-9.96% and 3.33-6.26%, respectively. Diacetyl, butyric acid, 2-acetyl-1-pyrroline, 1-octen-3-one and methional were identified at high intensities in cheeses. In addition, 'cooked', 'whey', 'creamy' and 'fermented' were defined as characteristic flavour terms for Circassian cheeses.Öğe Characterization of aroma-active compounds, sensory properties, and proteolysis in Ezine cheese(Elsevier Science Inc, 2009) Karagül Yüceer, Yonca; Tuncel, Barış; Güneşer, Onur; Engin, Burcu; İşleten, Müge; Yaşar, Kurban; Mendeş, MehmetEzine cheese is a white pickled cheese ripened in tin-plate containers for at least 8 mo. A mixture of milk from goat, sheep, and cow is used to make Ezine cheese. Ezine cheese has geographical indication status. The purposes of this study were to determine and compare the changes in basic composition, aroma, and sensory characteristics, and proteolytic activity of Ezine cheese stored in tinplate containers and plastic vacuum packages during storage. Aroma-active compounds were determined by thermal desorption gas chromatography olfactometry. To evaluate the proteolytic activity, casein and nitrogen fractions were determined. The results indicated that compounds identified at high intensities were dimethyl sulfide, ethyl butyrate, hexanal, ethyl pentanoate, (Z)-4-heptenal, 1-octen-3-one, acetic acid, butyric acid, and p-cresol. Characteristic descriptive terms were cooked, whey, creamy, animal-like, sour, and salty. The level of proteolysis increased in Ezine cheese during storage. Ezine cheese can be ripened in small-size packaging after 3 mo of storage. Approximately 6 mo is sufficient to produce the characteristic properties of Ezine cheese.Öğe CHEMICAL COMPOSITION AND ANTIOXIDANT CAPACITIES OF MOSSES GATHERED FROM MOUNT IDA (CANAKKALE, TURKEY)(Parlar Scientific Publications (P S P), 2019) Yayıntaş, Özlem; Özyurt, Dilek; Demirata, Birsen; Karagül Yüceer, Yonca; Yılmaz, SelehattinFour species of bryophytes were used as material and were gathered from various areas in Mount Ida (Kazdag), Canakkale, Turkey. Volatile compounds were isolated from the moss species with solid phase microextraction (SPME). GC-MS was applied to determine volatiles. The antioxidant capacity of bryophytes was established using CERAC and CUPRAC techniques. Trolox equivalent (TEAC) of aqueous extract of bryophytes was determined at concentrations of 0.0109 (+/- 0.0008)-0.0212 (+/- 0.0009) mmol trolox/g bryophyte and 70% methyl alcohol extract 0.0259 (+/- 0.0013)-0.0058 (+/- 0.0012) mmol trolox/g bryophyte using the CERAC technique and for water extract as 0.0027 (+/- 0.0006)-0.0083 (+/- 0.0012) mmol trolox/g bryophyte and methanol extract 0.0035-0.0095 (+/- 0.0005) mmol trolox/g bryophyte using the CUPRAC technique. The total flavonoid content was analyzed as equivalent mmol catechin/g bryophyte with the AlCl3/NaNO2 colorimetry technique. The total phenolic content of the species was analyzed with a Folin-Ciocalteu spectrophotometric technique.Öğe Chemical composition, antimicrobial, antioxidant and anthocyanin activities of mosses (Cinclidotus fontinaloides (Hedw.) P.Beauv. and Palustriella commutata (Hedw.) Ochyra) gathered from Turkey(Taylor & Francis Ltd, 2017) Tonguç Yayıntaş, Özlem; Alpaslan, Duygu; Karagül Yüceer, Yonca; Yılmaz, Selehattin; Şahiner, NurettinCinclidotus fontinaloides (Hedw.) P. Beauv. and Palustriella commutata (Hedw.) Ochyra were used in this study. The chemical composition of mosses in the ethanol and water extract was determined using GC-MS and FT-IR. Antioxidant activities of moss extracts were tested by total phenol and ABTS methods. Trolox equivalent value (TEAC) of mosses was calculated as 26 +/- 0.32 and 10 +/- 0.22 mg/g. The amounts of the flavonoid compounds were calculated as mg gallic acid. Gallic acid equivalent value of mosses was calculated as 587 +/- 0.55 and 496 +/- 0.22 mg/g. The extracts antimicrobial activity was tested against Escherichia coli (ATCC 8739), Bacillus subtilis (ATCC 6633), Staphylococcus aureus (ATCC 6538), Pseudomonas aeruginosa (ATCC 10145) and Candida albicans (ATCC 10231). Significant antibacterial effect was observed for C. fontinaloides and P. commutata in ethanol extract. Total anthocyanin activities of C. fontinaloides and P. commutata were determined as 50 +/- 0.17 and 144 +/- 0.33 mg/L.Öğe Chemical, microbial, and volatile changes of water kefir during fermentation with economic substrates(Springer Science and Business Media Deutschland GmbH, 2023) Gökırmaklı, Çağlar; Karagül Yüceer, Yonca; Güzel-Seydim, Zeynep BanuWater kefir is a plant-based type of kefir and has significant differences from well-known milk kefir. Recently, various complicated substrates were fermented with water kefir grains, but an economical substrate is essential for the industrial aspect. This study aims to understand changes in fermentation products of water kefir grains during fermentation with economic substrates and investigates how fermentation progresses under almost ideal fermentation parameters. The fig-based medium provided high contents of Lactobacillus spp. and Lactococcus spp. Also, fig-based medium with high fructose content contained a higher amount of Bifidobacterium sp. Moreover, the fig-based medium resulted in more organic acid content, forming as much as ten times higher than the sugar-based medium for lactic acid after the same fermentation time (p < 0.05). On the other hand, volatile compounds such as acetaldehyde, ethyl acetate, ethanol, acetic acid, 2-ethyl-1-hexanol, oxime-, methoxy-phenyl, and phenylethyl alcohol were detected for both water kefir samples. Antioxidant capacity (TEAC and ORAC) was higher for the fig-based medium than for the sugar-based medium. This is the first study that comprehensively proved that only sugar solution was not a sufficient medium for water kefir fermentation, but fig containing solution had abundant nutrients to obtain preferable and acceptable water kefir beverage.Öğe Comparative analysis of essential oil oleogels containing beeswax and sunflower wax with petrolatum gels(Wiley, 2024) Çokay, Hatice; Çelebi Uzkuç, N. Merve; Karagül Yüceer, Yonca; Öğütcü, MustafaIn this study, three different oil (black seed, St. John's Wort, and grape seed oils [GSO]) oleogels, which are especially used in complementary medicine, were produced with natural waxes (sunflower and beeswax [BW]). The physicochemical, textural, thermal, and structural features and volatile composition of the oleogels were determined and compared with commercial petrolatum gels (control sample). The sunflower and BW gels had a higher melting point than the petrolatum gels. Particularly, the firmness values of the fresh sunflower and BW oleogels were close to the petrolatum gels, except for the BW-based St John's Wort and GSO gels. The firmness and stickiness values of the oleogels and the control samples increased in relation to the storage period. The increase in firmness value was less in the sunflower wax than in the BW and control samples. All sunflower, BW and petrolatum gels exhibited the beta ' form. Volatile component data showed that different waxes have different volatile adsorption capacities. As a result, natural wax oleogels produced with various essential oils could be an alternative to similar products used in the cosmetics, pharmacology, and food supplement industries, which are already commercially available.Practical applications: (Oleogels have become a popular technique for structuring oils in recent years. In this way, oleogels are considered an alternative to solid fat such as margarine, butter, and shortening and an oil-restricting agent against oil leakage in oil-based foods. Consumers establish a close relationship between their own health and the foods they consume and the cosmetics they use. This situation has led to an increasing interest in natural products. Essential oils (EOs) are used in many fields, ranging from cosmetics to complementary medicine. In this context, essential oleogels produced with natural waxes were compared with the commercial products, revealing their potential for use in both cosmetic and food supplements. EO-oleogels represent a new approach to the oleogel product range with high commercialization potential for related industries.) Graphical Abstract: The textural and structural properties of the essential oil oleogels prepared with beeswax and sunflower wax were almost similar to their commercial counterparts such as petrolatum. imageÖğe Consumer attıtudes and factors affecting buying decision for functional foods(Gıda Teknolojisi Derneği, 2007) İşleten Hoşoğlu, Müge; Karagül Yüceer, Yonca; Yılmaz, Emin; Mendeş, MehmetGünümüzde tüketiciler gıdalardan sağlık üzerine olumlu katkı sağlayan ve hastalıkları önleyici etkiler beklemektedir. Bunun sonucu olarak, sağlık üzerinde olumlu etkisi olan fonksiyonel gıdalara talep gittikçe artmaktadır. Bu çalışmada, tüketicilerin bu tür gıdalara olan taleplerinin, cinsiyet, yaş, eğitim seviyesi, sağlık durumları, gıdaların fiyat ve etiket bilgileri gibi faktörlere bağlı olarak değişimin araştırılması hedeflenmiştir. Bu çalışma 9 adet sorudan oluşan bir anket çalışması olup, yaşları 20-60 arasında olan 249 kişi üzerinde yürütülmüştür. Ankete katılanların fonksiyonel gıdalara olan taleplerinin dikkate alınan faktörlere göre değişimlerinin ortaya konulabilmesi amacıyla çoklu uyum analizi tekniğinden yararlanılmıştır. Yapılan çoklu uyum analizleri sonucunda, genç tüketicilerin beslenme alışkanlıklarının sağlık üzerine etkisiyle ilgilenmedikleri görülmüştür. Diğer taraftan, beslenmenin sağlık üzerine etkisi olduğu düşüncesinin yaşla birlikte artma eğiliminde olduğu gözlenmiştir. Genç ve orta yaşlı tüketicilerin gıdaların etiketleri üzerindeki besin ve enerji değerlerini inceledikleri ve bu durumun özellikle bayanlarda çok daha belirgin olduğu görülmüştür. Tüketicilerin eğitim seviyesi arttıkça beslenme alışkanlıklarında sağlık ön plana çıkmaya başlamıştır.Öğe Consumer Expectation and Preference of Ezine Cheese(Univ Namik Kemal, 2013) Delice, N. Y.; Güneşer, Onur; Karagül Yüceer, YoncaThe objective of this study was to determine the preferences and purchasing behaviors of consumers of Ezine cheese. Consumer acceptance tests on two representative Ezine cheeses and face to face interviews were conducted in Canakkale-Turkey. Data provided from both tests were evaluated by Analysis of Variance and K-Means Cluster Analysis. Our data showed that Ezine cheese is mainly preferred for breakfast. Most consumers purchased Ezine cheese at least once a week. Our data detected a positive relationship between consumer age and acceptance of Ezine cheese. The age group 60-69 years old most preferred both cheeses. Statistical analysis clustered the Ezine cheese consumers into four groups, and significant differences were observed among the clusters with regards to consumption and purchasing behaviors. Cheese flavor and overall liking appear to be the most important factors for consumption. Asa result, habits of cheese consumption, benefits of dairy products, and enhancement of breakfast choices influenced consumer decisions for purchasing Ezine cheese.Öğe Different Bioengineering Approaches on Production of Bioflavor Compounds(Elsevier, 2018) İşleten Hoşoğlu, Müge; Güneşer, Onur; Karagül Yüceer, YoncaFlavor compounds are generally used as food additives and mostly produced through artificial means-that is, chemical synthesis or by extraction from plant and animal sources. The increasing consumer preference for natural products has promoted significant efforts toward the biotechnological production of these compounds (bioflavor). There are two kinds of aroma and flavor production via biotechnological process, de novo microbial processes and bioconversions of natural precursors using microbial cells or enzymes. The production of bioflavors with microorganisms and enzymes is illustrated by the discussion of the current state of the art developments in this field. Efforts at production of flavor compounds often lack economic profitability, mainly due to low productivities or low concentrations of target compounds in fermentation broth. This chapter reviews also the current state of the art of bioprocess used for the production of flavor and fragrance compounds, with emphasis on different ways used to improve process productivity. Bioengineering provides promising technical options for increasing the productivity with bioflavor production, such as different fermentation strategies (batch, fed-batch, and continuous fermentation), gas-phase or two-phase reactions, specific reactor constructions such as membrane, solid-state or closed loop reactors, optimization and modeling approaches of bioprocess and in situ recovery of product. © 2018 Elsevier Inc. All rights reserved.Öğe Effect of Feed Restriction on Some Chemical and Sensory Properties of Chicken Meat(Ankara Univ, Fac Agr, 2014) Dincer, Ecmel; Ulutas Parlak, Sibel; Engin, Burcu; Karagül Yüceer, Yonca; Mendes, MehmetFeed restriction application in the early stage of growth in broiler is common to prevent some health problems. However, feed restriction may affect the quality of meat. The objective of this study was to determine the effects of feed restriction on sensory properties of chicken meat. Total 60 Ross 308 broiler chickens were divided into three groups. The chickens in the first group were fed ad libitum (control group; AD), whereas the chickens in the second and the third group were exposed to two different feed restriction applications. The chickens in the second group (FR) were fed with 20% less food of ad libitum food intake, while the chickens in the third group (NF) were not fed between 9 am-3 pm. Feed restriction in both groups was applied when the chickens were between 7-21 days old. The chickens were slaughtered at week six of the trial and the carcasses were stored at -25 degrees C until chemical and sensory analyses. Descriptive sensory analysis was conducted to determine characteristic descriptive terms for breast and thigh body parts. In addition to sensory characteristics, some chemical properties including titratable acidity, dry matter and fat contents of the meat samples were determined. The data of chemical properties were analyzed by repeated measurement variance analysis, while the data of sensory evaluation were analyzed by multivariate analysis of variance (MANOVA) and multidimensional scaling (MDS). The finding of this study demonstrated that juicy, chicken flavor and umami were leading sensory characteristics of chicken meat. Some undesirable flavor attributes including cardboard, feed, oxidized and organy were also determined at very low intensities. Juiciness and chicken flavor scores of breast meat in AD and NF groups did not show any significant differences. No significant differences were detected between feed regimes in the flavor intensities of thigh meat. Feed restriction did not affect acidity or dry matter, whereas feed restriction affected fat contents of breast and thigh.Öğe Effect of ultraviolet light on water- and fat-soluble vitamins in cow and goat milk(Elsevier Science Inc, 2012) Güneşer, Onur; Karagül Yüceer, YoncaThe objective of this study was to investigate and compare the effects of UV light and heat treatment on vitamins A, B-2, C, and E in cow and goat milk. Vitamins were analyzed by reverse-phase high-pressure liquid chromatography. Ultraviolet and pasteurization treatments caused loss in vitamin C in milk. Pasteurization did not have any significant effect on vitamin B-2. However, UV light treatment decreased the amount of vitamin B2 after several passes of milk through the UV system. In addition, UV light treatment decreased the amount of vitamins A and E. Vitamins C and E are more sensitive to UV light. UV light sensitivities of vitamins were C > E > A > B-2. These results show that UV light treatment decreases the vitamin content in milk. Also, the number of passes through the UV system and the initial amount of vitamins in milk are important factors affecting vitamin levels.Öğe Effects of heat treatment, plant coagulant, and starter culture on sensory characteristics and volatile compounds of goat cheese(Elsevier Inc., 2023) Uzkuç, Hasan; Karagül Yüceer, YoncaThe effects of heat treatment, coagulant source, and starter culture addition on the physicochemical, sensory characteristics, and volatile compounds of goat cheese were evaluated. For this purpose, the goat cheese was produced from raw milk or heat-treated milk coagulated with Cynara cardunculus L. protease or calf rennet. The effect of the starter culture addition was also investigated. No significant differences were observed between the cheeses produced using different coagulants in terms of chemical, microbiological and sensory parameters, and proteolysis levels, but the combination of heat treatment and starter culture addition affected most of the attributes. A total of 27 volatile compounds, including acids, alcohols, esters, ketones, and aldehydes, were identified in the cheeses during ripening. Acidic compounds were the most abundant volatiles in cheeses. The raw milk cheeses had the highest sensory scores, while an unpleasantly bitter taste was recorded for the heat-treated and starter-free milk cheeses.Öğe Effects of spontaneous fermentation on Karalahna and Cabernet Sauvignon young red wines: volatile compounds, sensory profiles and identification of autochthonous yeasts(Springer, 2020) Çelebi Uzkuç, Nesrin Merve; Şişli, Burcu; Ay, Mustafa; Özmen Togay, Sine; Karagül Yüceer, Yonca; Bayhan, Aslı; Kırca Toklucu, Ayşegült The purposes of the present study were to evaluate the volatile compounds and sensory characteristics of young red wines produced by spontaneous and inoculated fermentations of Karalahna (KL) and Cabernet Sauvignon (CS) grapes and to identify the yeasts responsible for spontaneous fermentation by molecular methods. A total of 28 volatile compounds in KL wines and 35 compounds in CS wines were identified and quantified by GC-MS. The concentration of higher alcohols and esters differed significantly among spontaneously fermented and inoculated wines. Spontaneous fermentation resulted in greater amount of higher alcohols in KL wines, while inoculated wines had greater amount of higher alcohols in CS wines. Spontaneously fermented KL and CS wines showed greater amounts of esters than inoculated wines. KL wines obtained by spontaneous fermentation had significantly higher scores than inoculated wines based on fruity and green aromas, body and overall impression. Spontaneously fermented CS wines were found significantly higher in fruity and floral aromas than inoculated wines.Öğe Effects of ultraviolet light and ultrasound on microbial quality and aroma-active components of milk(Wiley, 2012) Engin, Burcu; Karagül Yüceer, YoncaBACKGROUND: Heat treatment is the most common way to extend the shelf life of milk. However, alternative technologies such as ultraviolet (UV) light and ultrasound (US), which are non-thermal methods for processing milk, have been developed to replace heat treatment. These technologies do not have any adverse effects on the quality of milk. The major purpose of this study was to investigate the effects of UV and US on different micro-organism groups and aroma compounds in milk. RESULTS: Heat pasteurisation at 65 degrees C for 30 min was used as thermal control treatment. The growth of total coliform group bacteria, Escherichia coli and Staphylococcus spp. was completely reduced by UV treatment. Application of USwas not sufficient to reduce the numbers of yeasts and moulds. In neutral/ basic fractions, 3-methylthiophene (plastic), hexanal (grass) and 1-hexen-3-one (floral) were major volatiles in milk samples. CONCLUSION: UV had a major effect on total coliforms, E. coli and Staphylococcus spp., but US was not as effective as UV and heat treatment in reducing certain groups of micro-organisms. No major differences were observed in terms of aroma-active compounds and flavour of milk following the different treatments. However, some new volatiles and change in rheological properties were generated by UV and US treatments. (C) 2011 Society of Chemical IndustryÖğe ENGINEERING OF MILK-BASED BEVERAGES: CURRENT STATUS, DEVELOPMENTS, AND CONSUMER TRENDS(Woodhead Publ Ltd, 2019) Güneşer, Onur; İşleten Hoşoğlu, Müge; Aydeniz Güneşer, Buket; Karagül Yüceer, Yonca[Anstract Not Available]
